A new study shows adolescent girls who receive the human papillomavirus (HPV) vaccine are no more likely to show signs they may be engaging in sexual activity than girls who forgo the shot. The data may help quell fears that surfaced in previous surveys indicating that some parents believe that their daughters may be more likely to engage in sexual activity if they receive the vaccine.
Two vaccines have been shown to protect against HPV--Merck's ($MRK) Gardasil and GlaxoSmithKline's ($GSK) Cervarix. Both vaccines made the top-selling list for the first half of 2012, but sales could be better. Just last month, the European Centre for Disease Prevention and Control announced that in 19 EU countries with HPV vaccine programs, vaccination rates were as low as 17% in some. And in the U.S. in 2010, only 32% of girls ages 13 to 17 received all three HPV vaccine doses.
Gardasil brought in $608 million in sales, compared with Cervarix's $285 million in the first half of the year.
Surveys have illuminated the stigma that receiving the shot raises the chances of a girl engaging in sex. "Some parents are concerned that saying 'yes' to the HPV vaccine is also encouraging teenagers to say 'yes' to sex," Dr. Carol Ford, chief of the Craig Dalsimer division of adolescent medicine at the Children's Hospital of Philadelphia, told ABC News.
Researchers from Emory University followed electronic data of nearly 1,400 girls aged 11 and 12 between July 2006 and December 2010 to see whether they received at least one dose of the vaccine within the first year and whether they were later counseled about contraception, acquired a sexually transmitted disease or became pregnant, according to the study published in the journal Pediatrics. The nearly 500 girls who received the vaccine were no more likely to be diagnosed with a sexually transmitted disease, discuss contraception or become pregnant than the just more than 900 girls who did not receive the shot, the study found.
"Those of us who work with adolescents are happy to use this information in discussing the vaccine with parents," Dr. Eve Shapiro, a pediatrician in Tucson, AZ, told ABC News.
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